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mrbro · March 26, 2011, 01:03 PM

C.U.P to PSI
If there is a relationship between these 2 standards you will not find it looking at the SAAMI maximum ratings for each cartridge. Reviewing the published spec some ratings stayed the same, some PSIs are higher than the CUP and some are lower. It appears that SAAMI either took a number of factors into account when making the new standards, or there other idiosyncracies with the test procedures that come into play.

Hornady Data
In my 4th edition of the manual, vol 1 page 74 describes the test methods. In that edition, to establish maximum loads, they used CUP when a test barrel was available, otherwise they read the signs on the primers and cases during load development. The actual load data came from chrono tests using the weapon listed for the caliber.

The 357 data in the 4th edition lists a max for AA#9 as 14.3g over a Fed 200 primer in a Hornady/Frontier case. Since this corresponds with the Lyman data and meets the standard that was in effect for over 50 years for that cartridge, I'd be comfortable with it as a maximum.

March 26, 2011, 01:03 PM	#16
mrbro member Join Date: September 14, 2008 Posts: 195	C.U.P to PSI If there is a relationship between these 2 standards you will not find it looking at the SAAMI maximum ratings for each cartridge. Reviewing the published spec some ratings stayed the same, some PSIs are higher than the CUP and some are lower. It appears that SAAMI either took a number of factors into account when making the new standards, or there other idiosyncracies with the test procedures that come into play. Hornady Data In my 4th edition of the manual, vol 1 page 74 describes the test methods. In that edition, to establish maximum loads, they used CUP when a test barrel was available, otherwise they read the signs on the primers and cases during load development. The actual load data came from chrono tests using the weapon listed for the caliber. The 357 data in the 4th edition lists a max for AA#9 as 14.3g over a Fed 200 primer in a Hornady/Frontier case. Since this corresponds with the Lyman data and meets the standard that was in effect for over 50 years for that cartridge, I'd be comfortable with it as a maximum.